<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="utf-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <!-- 上述3个meta标签*必须*放在最前面，任何其他内容都*必须*跟随其后！ -->
    <title>Bootstrap 101 Template</title>

    <!-- Bootstrap -->
    <link href="https://cdn.jsdelivr.net/npm/bootstrap@3.3.7/dist/css/bootstrap.min.css" rel="stylesheet">

    <!-- HTML5 shim 和 Respond.js 是为了让 IE8 支持 HTML5 元素和媒体查询（media queries）功能 -->
    <!-- 警告：通过 file:// 协议（就是直接将 html 页面拖拽到浏览器中）访问页面时 Respond.js 不起作用 -->
    <!--[if lt IE 9]>
    <script src="https://cdn.jsdelivr.net/npm/html5shiv@3.7.3/dist/html5shiv.min.js"></script>
    <script src="https://cdn.jsdelivr.net/npm/respond.js@1.4.2/dest/respond.min.js"></script>
    <![endif]-->
    <link href="//netdna.bootstrapcdn.com/font-awesome/4.7.0/css/font-awesome.min.css" rel="stylesheet">
</head>
<body>
<h1>你好，世界！</h1>
<a class="btn btn-default" href="#" role="button">Link</a>
<button class="btn btn-default" type="submit">Button</button>
<input class="btn btn-default" type="button" value="Input">
<input class="btn btn-default" type="submit" value="Submit">

<button class="btn btn-default">样式1</button>
<button class="btn btn-info">样式2</button>
<button class="btn btn-danger">样式3</button>
<button class="btn btn-warning">样式4</button>
<button class="btn btn-success">样式5</button>
<h1>不同尺寸的按钮</h1>
<button class="btn btn-warning btn-lg">样式4</button>
<button class="btn btn-warning btn-sm">样式4</button>
<button class="btn btn-warning btn-xs">样式4</button>
<h1>图片相关</h1>
<div STYLE="width: 200px;height: 200px">
    <img src="a.jpg" class="img-responsive" alt="">
    <img src="a.jpg" class="img-responsive img-circle" alt="">
    <img src="a.jpg" class="img-responsive img-rounded" alt="">
    <img src="a.jpg" class="img-responsive img-thumbnail" alt="">
</div>

<h1>表单相关</h1>
<div style="width: 300px;margin: 0 auto;background-color: pink">
    <form>
        <div class="form-group">
            <label for="exampleInputEmail1">Email address</label>
            <input type="email" class="form-control" id="exampleInputEmail1" placeholder="Email">
        </div>
        <div class="form-group">
            <label for="exampleInputPassword1">Password</label>
            <input type="password" class="form-control" id="exampleInputPassword1" placeholder="Password">
        </div>
        <div class="form-group">
            <label for="exampleInputFile">File input</label>
            <input type="file" id="exampleInputFile">
            <p class="help-block">Example block-level help text here.</p>
        </div>
        <div class="checkbox">
            <label>
                <input type="checkbox"> Check me out
            </label>
        </div>
        <button type="submit" class="btn btn-default">Submit</button>
    </form>
</div>
<!-- jQuery (Bootstrap 的所有 JavaScript 插件都依赖 jQuery，所以必须放在前边) -->
<script src="https://cdn.jsdelivr.net/npm/jquery@1.12.4/dist/jquery.min.js"></script>
<!-- 加载 Bootstrap 的所有 JavaScript 插件。你也可以根据需要只加载单个插件。 -->
<script src="https://cdn.jsdelivr.net/npm/bootstrap@3.3.7/dist/js/bootstrap.min.js"></script>
</body>
</html>